This invention relates to the forming of shell goods, and particularly to forming confectionary or other such shell goods by filling a mold with a liquid molding media and then inverting the mold to drain most of such media from the mold while leaving the mold coated by a layer of the media. More particularly, the invention relates to the formation of a confectionery or other such shell in a captive mold plant wherein each mold is connected to a conveyor media, such as the commonly known link chain or serpentine belt.
Compared to a free mold plant, wherein each mold pushes preceding molds through key areas of a manufacturing process, a captive mold plant is desirable for many applications because a mold in a captive mold plant progresses through the plant in a tightly controlled manner obviating many mechanical and operational complexities which are involved with free mold plants. The captive mold plant is particularly advantageous where a multitier conveyor circuit is desired in order to minimize space requirements for economic reasons and the like.
A major factor in the effectiveness of the captive mold plant is the fact that the conveyor proceeds at a specifically controlled pace. However, this can be a detriment to the proper forming of a confectionery or other shell.
According to the shell-forming technique which is presently of interest, an upwardly open mold cavity is completely filled with a liquid confection, such as molten chocolate for example, and then quickly inverted, allowing the chocolate to drain uniformly down the sides of the mold cavity to produce a coating of chocolate over the interior surface of the mold cavity. As the chocolate coating cools, it solidifies to form a chocolate shell. However, if the mold is inverted too slowly, the liquid chocolate will remain in contact with the low or leading side of the mold considerably longer than the opposite side. This will result in a thicker coating of chocolate building up on the leading side of the mold, and result in an unsatisfactory shell. In the past, the speed at which a mold could be turned over to make the confectionery shell has been dictated by the geometry of the mold and of the turning point. Even with the most advantageous geometry, however, the turnover speed has been too slow to produce a thin, uniform, and truly desirable shell.
A typical prior art arrangement is shown in U.S. Pat. No. 3,067,859, entitled TILTING MECHANISM IN MOLD CONVEYORS IN PLANTS FOR MOLDING CHOCOLATE AND SIMILAR MASSES and issued on Dec. 11, 1962 to Jacobsen. In the Jacobsen mechanism, each mold is pivotally connected near its center to a conveyor chain and is provided with guide rollers near its ends for following guide rails. A recess in the guide rails causes the leading guide roller to drop into the recess while the conveyor chain pulls the midpoint of the mold over the leading roller, levering the trailing roller ahead of the leading roller and turning the mold over. As would be apparent to one skilled in the art, this is a relatively slow turnover process and depends upon the geometry of the tray and of the turning point. Depending upon the geometry actually used, the mold can actually pause during the mold turnover, causing a substantial build-up of chocolate on the leading side of the mold. As would also be apparent, it would be impractical, and not really feasible, to compensate for such geometry by periodically accelerating and decelerating the conveyor as each mold approaches and passes the turning point.